Strip feeding device



1959 I A. w. METZNER 2,873,838

' STRIP FEEDING DEVICE Filed March 1, 1955 I 4 Sheets-Sheet 1 VIII/1151HE INVENTOR. n4 ALBERT w. METZNER 5 WWW x4 TTOR/VEY Feb. 17, 1959 A. w.METZNER 2,873,838

STRIP FEEDING DEVICE Filed March 1, 1955 4 Sheets-Sheet 2 mm HIHHIHHHIINVENTOR.

ALBERT -W. METZ NER j lmm A TTOK/Vf Y Feb. 17, 1959 A. w. METZNER STRIPFEEDING DEVICE Filed March 1, 1955 4 Sheets-Sheet 3 b Illll Ill!llllllllllllll IN V EN TOR.

ALBERT W. M ETZNER g lmw A 7' TGPNE Y Feb. 17, 1959 A. w. METZNER2,873,838

4 Shecs-Sheet 4 INVENTOR.

ALBERT W. METZN ER ATTORNEY United States Patent STRIP FEEDING DEVICEApplication March 1, 1955, Serial No. 491,338

' 15 Claims. Cl. 197-126) This invention relates to strip feedingapparatus, and more particularly to a platen assembly forming a part2,873,838 Patented Feb. 11, 19 5 9 Fig. 3 is a view in top elevation ofthe assembly as shown in Fig. 2;

Fig. 4 is a view in cross section, taken substantially along the line4-4 of Fig. 3;

Fig. 5 is a view in cross section, taken substantially along the line 55of Fig. 3;

Fig. 6 is a view in cross section, taken substantially along the line6-6 of Fig. 3; there being shown in each of Figs. 4, 5 and 6 a type barof the typewriting machine in cooperative relation with the platenassembly;

Fig. 7 is a detail view of one of the pin feed devices,

I being a view in cross section through the shaft supporting of atypewriting or like machine or adapted for substitution therein for theconventional roller platen.

. The object of theinvention is to improve the construction as well asthe means and mode of operation of pin type strip feeding devices,whereby they may not only be economically manufactured, but will be moreefiicient in use, uniform in action and be unlikely to get out ofrepair.

I It is an object of the invention to facilitate installation and use ofa carbon ribbon or strip feeding attachment in the platen assembly.

Another object of the-invention is to adapt the use of carbon stripmaterial more readily to typewriting and like machines through use of anoverhead record strip feeding means featuring a novel escalator movementof feeding pins.

. A further object of the invention is to free the carbon strip materialand the record strip material intermittently for a more facile advancethereof.

Still another object of the invention is to enable the surfacehardnessof the platen to be changed without substituting one platen element foranother in the machine.

. Still more specifically it is an object of the invention to provide aplaten member reciprocable bodily in its mountings for freeing of thestrip material and adjustable in a tilting direction to place differentportions thereof in the writing-line, it being proposed to coverdifferent portons of the platen with materials of respectively differenthardness.

It is still a further object to make the reciprocating movement of theplaten a machine initiated operation, occurring regularly as upon eachactuation of the line space mechanism, while the tilting adjustment ofthe platen is a selective, manually accomplished operation.

A further object of the invention is to provide a strip feeding deviceembodying the advantageous structural features, the inherent meritoriouscharacteristics and the mode of operation herein set forth, or theirequivalents.

With the above primary and other incidental objects in view as will morefully appear in the specification, the invention intended to beprotected by Letters Patent consists of the features of construction,the parts and combinations thereof, and the mode of operation,hereinafter described or illustrated in the accompanying drawings, ortheir equivalents.

In the accompanying drawings wherein is shown one but obviously notnecessary the only form of embodiment of the invention.

Fig. 1 is a view in perspective, showing a part of a typewriting or likemachine in dotted outline, with a platen assembly in accordance with theillustrated embodiment-of the invention installed therein;

Fig. 2 is a view in front elevation of the platen assembly of Fig. 1, aspool case for the carbon strip material being broken away;

such device;

Fig. 8 is a detail view of the platen in its advanced position in thewriting line;

Fig. 9 is a view like Fig. 8 showing the platen member in retractedposition;

Fig. 10 is a view in detail and in cross section of the platen membershowing a replaceable platen element installed therein;

Fig. 11 is a view like Fig. 10 showing the replaceable platen elementreleased from the support therefor;

Fig. 12 is a detail view in cross section of a replaceable platenelement showing an alternate covering construction for the face thereof;and Fig. 13 is a detail view of a modified platen structure in which theplaten is adjustable in tilting directions to bring different parts ofthe replaceable platen element of Fig. 12 to the writing line.

Like parts are indicated by similar characters of reference throughoutthe several view-s.

Referring to the drawings,.part of a typewriter is shown in Fig. 1 indotted outline with a platen assembly in accordance with the illustratedembodiment of the invention shown substituted therein. In effecting suchsubstitution it is necessary merely to lift the machine equipped rollerplaten out of its place in the carriage and replace it with the instantassembly. Thus, a main support shaft 10 (Fig. 2) has spacer sleeves 11and 12 at opposite ends thereof mounted on the shaft and centeringbearings 13 which are received into races in the typewriter carriage inthe same manner that corresponding parts of the conventional platenroller shaft are received.

The platen assembly includes spaced apart side frames 14 and 15 mountedon the shaft 10 and rigidly held apart by interconnecting rods andshafts, to be described. A ratchet wheel 16 (Fig. 4) is secured to theshaft 10 and is acted upon by a pawl 17 connected through a rock arm 18and a link 19 to the line space mechanism of the machine. The arm 18pivots about the shaft 10, being secured to a sleeve 20 rotatablymounted on the shaft 10. One end of the arm 18 carries the pawl 17 whilethe other end is connected to the link 19. The link 19 extends into themachine for intermittent machine operation, as for example upon eachcarriage reciprocation. In response to a reciprocating movement of thelink 19, as effected upon its intermittent machine operation, the arm 18is oscillated and is effective through pawl 17 and ratchet 16 to turnthe shaft 10 one increment of rotary motion. The shaft 10 also may beturned by knobs 21 and 22 on the opposite ends thereof, the latter ofwhich is connected in the, assembly through an internal shaft 23 andvariable24 and is effective in the usual manner in apparatus of thiskind to initially locate the writing line with respect to the platen.

The platen is in the form of a bar 25 extending between the side frames14 and- 15 and supported thereby in a manner later to be described. Thefront surface of the bar 25, which is generally rectangular in shape, isformed with a ledge 26 at its lower edge undercut to define a channel27. A platen element 28 has a baseportion for resitigniaa n intima e.contact th h front surface of the bar 25 and on its opposite side edgesare flanges, one of which is received in'the channel 27. The otherflange on element 2 8 is positioned to be engaged and held by a latch 29pivotally connected to upstanding brackets 31 on the top edge of the bar25 On the rearward side of the bar 25 is a series of brackets 32rotatably mounting a shaft 33. At longitudinally spaced apart pointstherealong cams 34 are fixed to the shaft 33, which cams have highportions arranged to underlie a rearwardly extending part 35 of thelatch 29 and so hold the latch in the effective, platen locking positionshown in Fig. 10. On one end of the shaft 33 is a lever 36 manipulativeto rock the shaft 33 and thereby the cams 34. The high portions of theearns 34 may'thus be moved out of cooperative relation with the part 35of latch 29 and the latch thereby released for opening movement andremoval of the platen element 28, as indicated in Fig. 11.

The outer or front surface of the platen element 28 is curved in an arcconforming to the curvature of the platen roller replaced. Such surface,moreover, is overlaid by a relatively soft rubber or rubberlike material37. The requirements of the work may at some times be such that theimpact surface of the platen, as represented by the material 37, berelatively soft and at other times require that such surface berelatively hard. To make such a change it is necessary merely to removeone platen element 28 and replace it with another, in the manner thathas been described.

A manifold record strip 38 reaches cooperative relation with the platenassembly from the rear thereof, as indicated in Figs. 4, and 6, passingbeneath the assembly over friction rolls 39 and 41 secured respectivelyto shafts 42 and 43 journaled in the side frames 14 and 1.5 near thebottom edge thereof and below the horizontal plane of the platen bar 25.From the friction rolls 39 and 41, the strip 38 extends over the frontof the platen element 23 where it may be struck by type bars 44, theplaten element and bar 25 rigidly sustaining the impact of the printingaction. Beyond the platen element 28, the strip 38 is guided insubstantially a vertical path by guides 45 dependent from a cross bar 46extending between uprights 47 and 48 on the side frames 14 and 15. Thestrip is again directed rearwardly over the curved upper ends of theguide arms 45 out of the machine or toward a place of storage.

A shaft 49 is rotatably mounted in the side frames 14 and and at one endprojects through the frame 14. The projecting end thereof, as seen inFig. 1, mounts a gear 51 meshing with a similar gear 52 on the shaft 10.Also on the shaft 49, between the frames 14 and 15, is another gear 53(Fig. 6) meshing with a gear 54 on the previously mentioned shaft 42carrying the friction feed roll 39. Through an idler gear 55'the gear 54drives another gear 56 made fast to the shaft 43 on which is thefriction feed roll 41. The feed rolls 39 and 41 are, through thedescribed construction and arrangement of parts, caused to rotate or toadvance in accompaniment with motion of the shaft 16. Cooperable withthe feed rolls 39 and 4-1 are friction rolls 57 and 58 carried by apaper pan 59 mounted in underlying relation to the platen assembly as apart of the conventional machine structure. The strip 33 is guidedbetween the paper pan 59 and the feed rolls 39 and 41, and, as is wellknown in the typewriting art, the pan 59 is adjustable to alternatepositions illustrated respectively herein in Figs. 4 and 6. In the Fig.4 position, rotation of the friction feed rolls 39 and 41 is with outeffect on the strip 38. cooperatively engaged with the rolls 57 and 58of the paper pan 59 in the manner shown in Fig. 6, however, rotation ofthe friction feed rolls is effective to advance the strip 38 upwardlyover the platen.

Also mounted; on the shaft 49 between the side frames 14 and 15 is agear 61 (Fig. 5) meshing with another gear 62 fast on a shaft63alsoextending between the side frames 14 and 15. In the case of theshaft 63, however, the ends of such shaft have rollers 64 thereonresting on a track 65 on the upper edge of each side frame 14 and 15. Atits one end, the track 65 terminates in a recess 66 and at its other endin a hooked recess 67, in the latter of which the shaft 63 is yieldinglyheld by a spring detent 67. The arrangement is such,-it will beunderstood, that the shaft 63 is bodily shiftable in a to and frodirection between extremes as represented by the recesses 66 and 67.

On the shaft 63 is a pair of pin feeding devices for positive engagementwith and advancement of the strip. Such devices, indicated respectivelyat 68 and 69, are identical in construction so that a description of onewill suffice for both. Thus, each device is mounted between and may besaid to include a pair of arms 71 and 72 which at their one ends arepivotally mounted on the shaft 49'and at their other ends have the shaft63 passed therethrough. Between the arms 71 and 72 are spaced apartdiscs 73 and 74, the former being concentric to the shaft 63 and havinga hub 75 extending through the arm 71 and carrying an adjustable screwstud 76. The tip end of the screw stud 76 is formed as a key 77 and isreceived in a longitudinal slot or keyway 78 in the shaft 63.

Rotation of the shaft 63, through the meshing gears 61 and 62, thus ispartaken of by the disc 73. Also, the pin wheel assembly, it will beunderstood, may be released for longitudinal adjustment along the shaft63 by loosening the screw stud 76, the pin wheel assembly being securedin its newly adjusted position by turning the screw stud down intofrictional contact with the shaft 63.

The disc 74 is in eccentric relation to the shaft 63 and to itscompanion disc 73, and has the shape of a ring through which the shaft63 passes and which is rotatably mounted on an eccentric boss formationon a plate 79 on the arm 72. Interposed between the discs 73 and 74 is aseries of feeding pins 81 comprising links or base portions 32, and,substantially normal thereto, pin portions 83. Each base portion 82 isconnected at its one end to the disc 73 and at its other end to the disc74, the connections in both instances being pivotal ones. The disc 74 isrotated by the disc 73 through the pins 81 and it will be understoodthat in the course of such rotation the several pins 81 will maintainthe positions illustrated, with the pin portions 83 substantiallyparallel to one another. As indicated in Figs. 4 and 5, the motion ofthe pin portions 83 of the feeding pins as they approach and enterperforations in the strip 38 is in substantially a straight line, as isthe retracting motion relatively to the strip. As a result, stripperforations more nearly conforming in diameter to the specific diameterof the pin portions of the feeding pins are possible resulting in closerand more accurate registration of manifold forms.

The shaft 63 mounting the pin feed devices 68 and 69 is, as beforedescribed, shiftable in to and fro directions to place the rollers 64thereon alternately in 66 and 67. In the former position the pin feeddevices occupy a forward position as shown in Figs. 4 and 5 wherein thefeeding pins are effective to engage the strip. This position of theparts is considered the operating or feeding position, with respect tothe pin feed devices. Positioned as shown in Fig.6, the pin feed devicesare out of position to engage the strip and so occupy what may be termednon-operating position.

In the non-operating position of the pin feed devices, the paper pan 59usually will be adjusted for frictional feeding of the strip. Similarlywhen the paper pan 5) is adjusted to an inefiective position, the pinfeed devices usually will be set in operating position for positive pinfed advancement of the strip.

The side arms 71 and 72 of each pin feeding device, are interconnectedby tie members 84 which make of the elements 71, 72, 73, 74 and 79, asWell as the feeding pins 81, a unitary assembly.

, Guide or feed fingers 85 may be mounted on the respective pin feedingdevices to hold the marginally perforated strip in engagement with thefeeding pins during the pin feeding operation.

The platen assembly further includes means for supporting and advancingcarbon strip or ribbon material in transverse interleaved relation tothe record strip material 38 for the making of multiple copies of theimpression delivered by the type bar 44. Thus, manifold carbon ribbonmaterial 86 is led from a spool suitably mounted in or near thetypewriting machine to and around roller means 87 mounted on a bracket88 secured to side frame member 15. From the roller means 87, the carbonribbon material 86 extends transversely across the front of the platenassembly in adjacent parallel relation to the platen element 28 and, atthe opposite end of the platen assembly, enters a case 89 mounted onbracket 91 secured to side frame member 14. Within the case 89 areintermeshing gear-like feeding members 92 and 93. As indicated in Fig.2, the carbon ribbon material passes between the intermeshing members 92and 93 and extends through an opening 94 in the case 89. In response torotation of the members 92 and 93 the carbon ribbon material is advancedacross the front of the platen assembly, into the case 89 and out of theopening 94 to another spool or place of disposal.

The feed member 92 is secured to a shaft 95 journaled in top and bottomwalls of the case 89. The feed member 93 is similarly secured to a shaft96, the opposite ends of which are received in opposed slots 97 in thetop and bottom walls of the case 89. At its upper end, the shaft 96 hasa plate 98 secured thereto formed with a detent portion for engagementin spaced apart recesses 99 in case 89. A frame comprising arms 100 and101 on another shaft 102 supports the shaft 96 and feed member 93thereon in an upright position. Adjustment of the plate 98, to itsdifferent detented positions, it will be understood, serves to engageand disengage the feeding member 93 from its companion member 92. Thus,in a retracted position, a path is open between the feed members forinstallation of the carbon ribbon. In the advanced position of the feedmember the carbon ribbon is clamped between the members 92 and 93 and sois advanced or fed out of the opening 94 in response to and inaccompaniment with rotation of the feed members. The member 92 operatesas the driving element of the carbon ribbon feed mechanism, there beingsecured to the underside thereof a ratchet 103. An actuating lever 104has one end pivotally connected to the shaft 95 and its other endpivotally connected to the aforementioned link 19. A pawl 105 is mountedon the lever 104 between its ends and engages the teeth of ratchet 103.Upon each reciprocation of the link 19, therefore, the lever 104 isrocked and the gear-like feed member 92 turned one increment of movementunder the urging of pawl 105. A corresponding advance of the carbonribbon material 86 across the face of the platen accordingly occurs uponeach operation of the line space mechanism or whatever other machineinstrumentality may be used for reciprocation of the link 19. A pawl 106is mounted on the bottom wall of case 89 and is engageable with theratchet 103 to prevent back lash or return motion of the ratchet andassociated parts.

Returning to a consideration of the platen bar 25, the opposite ends ofsuch bar are rigidly connected to the outer ends of respective arms 107,'the inner ends of which are formed with rectangular recesses 108through which passes the shaft and previously considered sleeve 20thereon. In the upper edge of each slot 108 is a recess 109 receiving afinger 111 formed integrally with or otherwise secured to the sleeve 20.It will be apparent that a rocking motion of the sleeve 20 in acounterclockwise direction, as from the position of Fig. 8 to theposition of Fig. 9, will result in a bodily shifting or retractingmotion of the arms 107 and platen means carried thereby. Similarly, areturn rocking motion of the sleeve 20 in a clockwise direction, as fromthe position of Fig. 9 to the position of Fig. 8, serves to return oradvance the arms 107 and platen means from retracted position. Thesleeve 20, as has heretofore been seen, is connected to the arm 18 androcks in accompaniment with reciprocation of the link 19. Machineoperated reciprocation of the link 19 accordingly results in and isaccompanied by an oscillatory movement of the sleeve 20 and hence abodily shifting movement of the platen bar 25 and element 28 carriedthereby.

Each arm 107 has a laterally projecting pin 112 received in ahorizontally extending slot 113 in respec tive side frames 14 and 15.The slots 113 lie in a horizontal line running through the shaft 10 andthe medial horizontal point of intersection of the record strip material38 and the carbon ribbon strip material 86, such line further passingthrough the medial horizontal plane of the type on type member 44positioned as illustrated in the drawing with such type member at thelimit of its upward stroke as defined by a machine abutment 114. Theplaten bar 25 and element 28 are retracted and advanced in the describedline, which may be termed the writing line of the machine. In the normalor advanced position of the platen a pressure may be considered to beexerted thereby on the strip material holding the record strips and thecarbon strips in intimately contacting relation. In the retractedposition of the platen such pressure is released, freeing the strips formore facile advance by their respective feeding devices. Movement of theplaten will, of course, occur in a timed relation to advancement of thestrips.

As shown in Fig. 12, in lieu of substituting one platen element 28 foranother to obtain a platen surface of different hardness there may beapplied thereto coverings of different hardness on upper and lowersurfaces of the curved front face of the platent element. Thus, as seenin Fig. 12, a platen element 115 constructed and used in the same manneras the element 28, has on the front face thereof separate upper andlower strips 116 and.117 of a rubber or rubberlike covering ofrespectively different hardness. As seen in Fig. 13, the element 115 isinstalled in a platen bar 118 in the same manner as the element 28 inposition to sustain impacts from a type bar 119. The platen bar 118 iscarried between arms 121 on a sleeve 122 mounted on a shaft 123 andoscillated in the same manner as the corresponding arms 107 of the firstconsidered embodiment of the invention. this instance is spring urged toa laterally projecting posi tion and is retractable by a knob 125. Eachof the side frames 14 and 15 has a medial horizontal slot 126corresponding to the slot 113 and on opposite sides thereof has upwardlyand downwardly diverging slots 127 and 128. Should there be installed inthe platen bar 118 a pl-aten element 28 of conventional construction thepins 124 would be located in the middle slot 126 and the operation ofthe device would be as above described. Should the platen element 115 beinstalled in the bar 118, however, the pins 124 would be adjusted toengage in one or the other of the slots 127 or 128. In the advancedposition of the platen means, therefore, either the upper covering 116or the lower covering 117 would be presented in cooperative relationwith the type member 119. To change from one position to another, ofcourse, the pins 124 are retracted out of one slot 126- 128 and the arms121 are rocked to bring a selected other slot into cooperative relationwith such pins. The described arrangement, it will be understood, makesit possible to substitute one platen hardness for another, as may bedesirable in changing from one number of multiple copies to another,without actually substituting one platen or one platen element foranother.

From the above description it will be apparent that there is thusprovided a device of the character described The arms 121 have'each aplunger 124 which in possessing the particular features of advantagebefore enumerated as desirable, but which obviously issusceptible ofmodification in its form, proportions, detail construction andarrangement of parts without departing from the principle involved orsacrificing any of its advantages.

While in order to comply withthe statute the invention has beendescribed in language more or less specific as to structural features,it is to be understood that the invention is not limited to the specificfeatures shown, but that the means and construction herein disclosedcomprise but one of several modes of putting the invention into effect,and the invention is therefore claimed in any of its forms ormodifications within the legitimate and valid scope of the appendedclaims.

Having thus described my invention, I claim:

1. In a typewriting or like machine having a carriage and a line spacemechanism operable upon each reciprocation of the carriage; thecombination of a platen reciprocable support means on said carriage forsaid platen, means for advancing manifold record strip material oversaid platen an increment of movement upon each operation of said linespace mechanism, means for advancing carbon ribbon material ininterleaved transverse relation to said record strip material anincrement of movement upon each operationof. said line space mechanism,and means for reciprocating said support means and said platen therewithin a medial horizontal plane common to said ribbon material, said platenand said support means upon each operation of the line space mechanism.

2. In a typewriting or like machine, a relatively stationary support,means for reciprocably mounting a platen bar assembly in said support,rotary pin feeding devices carried by said support in overhead relationto said platen bar assembly, said devices operating to pull manifoldrecord strip material over said platen bar assembly in a substantiallystraight line, carbon strip material in transverse interleaved relationto said record strip material, said means for reciprocably mounting saidplaten bar assembly lying in the medial horizontal plane of the Writingline of the machine, and means for intermittently reciprocating said barassembly relatively to said support for more facile advance of saidcarbon strip material.

3. A platen assembly for substitution as a unit in a typewriting or likemachine, including relatively stationary side frames, a platen extendingbetween said side frames and having parallel plate elements at theextremities thereof, strip feeding devices supported between said framesin substanially overhead relation to said platen and operable to advancea strip in substantially a planar path over said platen, and mountingmeans on said side frames engaging in said plate elements to providebearing means therefor and a linear movement thereof and providing forrelative retracting and advancing movements of said platen from andtoward the said planar path of said strip.

4. A platen assembly, including relatively stationary side frames, spoolmeans on said frames having carbon strip material wound thereon andextending in a substantially planar path between said frames, a platenbar extending between said side frames in parallel adjacent relation tosaid carbon strip material, strip feeding means supported between saidside frames in substantially overhead relation to said platen bar andoperable to advance record strip material in substantially a planar pathpast said platen bar and at substantially right angles to the path ofsaid carbon strip material, said record strip material and said carbonstrip material being interleaved, and mounting means for said platen barin said frames, said mounting means having a medial horizontal plane incommon with the type to be presented to said platen bar in use andproviding for linear reciprocation of said platen bar in said plane formore facile feeding of the strip material.

5. A platen assembly according to claim 4, characterized in that saidmounting further provides for tilting of said platen "bar selectively topresent upper and lower portions thereof in a writing line defined bythe medial line of intersection of saidrecord strip and carbon strip ma:terial.

6. In a typewriting machine or the like having a carriage and a linespacing mechanism operable on each reciprocation of the carriage; asupport means on said carriage, a platen bar, support elements mountingsaidplaten bar and mounted on said support means in relatively.containing relation thereto, said support elements being freelyadjustable relative said support means in a reciprocable sense, andmeans mounted on said support means and responsive to the operation ofthe line spacing mechanism to reciprocate said support elements and saidplaten bar thereby.

7. In a typewriting or like machine having a carriage and a line spacemechanism operable on each reciprocation of the carriage; thecombination of a platen, support means for said platen, means shiftablymounting said v platen and said support means therefor for reciprocationon said carriage in a plane defined by the longitudinal central axes ofsaid platen and said mounting means, and means for effecting theshifting of said platen on each operation of the line spacing mechanism.

8. In a typewriting or like machine having a carriage and a line spacemechanism operable on each reciprocation of the carriage; a platen, asupport means on said carriage, means mounted in free bearing relativelycontaining relation to said support means and mounting said platen inparallel relation tosaid support means, additional support elementsguiding said free bearing means and lying in a common medial horizontalplane of said free bearing means and said platen, and means forreciprocating said support means and said platen in said common plane onoperation of the line space mechanism.

9. In a typewriting or like machine having a carriage, and a line.spacing mechanism operable 0n reciprocation of the carriage; a supportshaft mounted on said carriage, support means in free bearing containingrelation tosaid shaft, a platen mounted to said support means inparallel relation to said shaft, and additional support means for saidplaten and said first mentioned support means lying in a common medialhorizontal plane thereof, said first mentioned support means and saidplaten being freely reciprocable in said common plane through meanseffective on operation of said line spacing mechanism.

10. In a typewriting or like machine having a carriage and a line spacemechanism operable upon each reciprocation of the carriage; a platen,plate means arranged in substantially parallel fashion and mounting saidplaten transversely thereof, said plate means having spaced alignedelongated apertures therethrough, support means for said plate'meansmounted on said carriage and projecting through said aligned aperturesto define a plane of reciprocation for said platen, and means forreciproeating said plate means and said platen thereby on operation ofthe line space mechanism.

11. In a typewriting or like machine having a carriage, and a line spacemechanism operative on each reciprocation of the carriage; a shaftreleasably mounted on said carriage, a sleeve on said shaft having cammeans externally thereof, said sleeve being operatively connected to theline space mechanism, a pair of plate elements mounted to said shaft fordisplacement relative thereto in parallel planes perpendicular to saidshaft, a platen connecting said plate elements, and guide means on saidcarriage in the medial horizontal plane of the writing line of themachine and connected with said plate elements, said cam means engagingin said plate elements for reciprocation thereof on operation of theline space mechanism, and said guide means providing for movement of theplate elements and said platen in reciprocating fashion in said plane.

12. In a typewriting or like machine, a carriage, means defining awriting line, a platen bar, and means mounting said platen bar in saidcarriage for relative reciprocation 9 in the plane of said writing line,said means mounting said platen bar aifording means for selectiveadjustment of said platen bar to dispose a selected portion thereof of aparticular hardness in the plane of said writing line.

13. In a typewriting or the like machine, a support means, a platen bar,means mounting said platen bar to said support means in relativelycontaining reciprocable relation thereto, parallel side plates disposedat either end of said platen bar, selective guide means in said sideplates, and means providing for selective connection of said mountingmeans in said guide means to dispose a selected portion of said platenbar for reciprocation in the writing line of the machine.

14. In a typewriting or like machine, a platen bar, said platen barconsisting of longitudinally arranged parallel strips of material ofrelatively varying hardness, side plates to either end of said platenbar, slots in said side plates in vertically displaced fashion, andmeans selectively connecting said platen bar in the respective slots andreciprocable therein, said selective connection establishing aparticular strip of the platen bar in a writing line of the machine forreciprocation in a plane defined by said selective connecting means andsaid writing line.

15. In a typewriting or like machine having a stationary frame; asupport shaft releasably mounted to said frame, a platen bar havinglongitudinal portions of varying hardness, parallel support armsmounting said platen bar in parallel relation to said support shaft forrotation and reciprocation relative thereto, side frames mounted to saidstationary frame and provided with vertically displaced slots therein,and means selectively connecting said arms to said side frames andselectively engaged in the slots therein to dispose a particular portionof said platen bar for reciprocation in a plane defined by said shaft,said selective connecting means and the writing line of the machine.

References Cited in the file of this patent UNITED STATES PATENTS335,972 Slocum Feb. 9, 1886 1,890,563 Degener Dec. 13, 1932 1,917,100Degener July 4, 1933 2,293,769 Sherman Aug. 25, 1942 2,506,701 ChisholmMay 9, 1950

